<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        /* 选不选中 css 状态 */
        .custom-text-selection::selection{
            color: aqua;
            background: deeppink;
        }
        *{
            margin: 0;
            padding: 0;
        }
        body{
            /* < 480 mobile */
            min-width: 550px;  /* pc  */
            font-weight: bold;
            font-size: 20px;
        }
        #header,#footer{
            background: rgba(29,29,27,0.726);
            text-align: center;
            line-height: 60px;
            height: 60px;
        }
        #container{
            padding-left: 200px;
            padding-right: 150px;
            overflow: hidden;
        }
        #container .column{
            position: relative;
            float: left;
            text-align: center;
            height: 300px;
            line-height: 300px;
        }
        #center{
            width: 100%;
            background: rgba(206,201,200,1);
        }
        #left{
            width: 200px;
            right: 200px;
            background: rgba(95,179,235,1);
            margin-left: -100%;
        }
        #right{
            width: 150px;
            background: rgb(231,105,2);
            right: -150px;
            margin-left: -150px;
        }
    </style>
</head>
<body>
    <!-- <p class="custom-text-selection">select some text</p> -->
    <div id="header">header</div>
    <div id="container">
        <!-- 三列式布局  中间的内容放在前面
        你是如何看到页面的，先看到中间，再看到两边
        -->
        <div id="center" class="column">center</div>
        <div id="left" class="column">left</div>
        <div id="right" class="column">right</div>
    </div>
    <div id="footer">footer</div>
</body>
</html>